Despite its compact size, each Compact Disc (CD) in its many forms (e.g., CD-ROM, CD-R, CD-RW, CD-DA, CD-I, etc.) can be used to store enormous amounts of data (i.e., 650 MB) including audio, text, software codes, graphics, etc. In addition, CDs are subject to no mechanical wear and tear and are therefore very reliable. As a result, CDs have become the preferred portable data storage format in recent years. Indeed, software products (e.g., application software, video games, etc.) are currently distributed by software publishers almost exclusively on CD-ROM format. However, it is estimated that software and video game publishers lose billions of dollars worldwide to product piracy each year. While most CD-ROM software piracy losses are attributable to counterfeiting by professional pirates, with the availability of CD Recordable (CD-R) drives at an affordable price, the average consumers can now make perfect copies of CD-ROM originals for the price of a blank disc.
One effective solution to the problem of unauthorized (illicit) software copying is provided by Macrovision Corporation of Sunnyvale, Calif. through its C-dilla Subsidiary. This anti-copy solution involves encrypting the executable file of the application (i.e., CD-ROM's software content) according to a production key and embedding a digital signature corresponding to the production key onto the CD-ROM during manufacturing. The hidden digital signature can only be detected using special authentication software provided with the CD-ROM at boot-up. Upon detecting and authenticating the digital signature, information in the digital signature is used as a key to decrypt the encrypted executable file of the software content thereby allowing the application to launch. If the digital signature is not detected, the encrypted executable file of application cannot be decrypted for launch. The digital signature is designed so that it cannot be copied. In other words, when a copy protected CD-ROM is copied to another CD or to a computer-readable storage drive (e.g., computer hard drive), the digital signature cannot be transferred to the copied CD or storage drive thereby preventing the copied application from being launched. Hence, a copied CD is essentially useless.
On the other hand, although the digital signature is not transferred to a computer-readable data storage device when the content of a copy-protected CD-ROM is copied into the storage device, the copied application can still be launched as long as the copy-protected CD-ROM remains in the CD-ROM drive because the digital signature residing in the copy-protected CD-ROM can still be detected and authenticated. By requiring the copy-protected CD-ROM to remain in the CD-ROM drive for the copied application in the storage device to be able to launch, illicit copying of a copy-protected CD-ROM into a storage device of someone other than the rights-owner is prevented. A rights-owner is defined as someone who is the rightful owner of the copy-protected CD-ROM. At the same time, the ability of the rights-owner to copy the content of the copy-protected CD-ROM into his computer-readable data storage device is basically preserved because, as the rights-owner, he is assumed to have the copy-protected CD-ROM readily available nearby. However, by requiring the copy-protected CD-ROM to be inserted into the CD-ROM drive each time to launch the copied application, the use of the CD-ROM drive may not be utilized by other applications. At the very least, this is an inconvenience. At worst, this prevents the rights-owner from concurrently using multiple applications that are copy-protected. Such inconvenience is exacerbated for laptop users because they are now required to bring along the application software CD-ROMs while traveling. As a result, software publishers are torn between the desire to protect their intellectual property and the desire to supply the consumers with user-friendly products. In this difficult position the software publishers are faced with either lost revenue from the illicit copying of their products or lost revenue from losing market share.
Thus, a need exists for an improved method to discourage illicit copying of a copy-protected CD-ROM into a computer-readable data storage device without requiring the copy-protected CD-ROM to be inserted in the CD-ROM drive to successfully launch the copied application from the data storage device.